BERLIN (Reuters) -- German Chancellor Angela Merkel said General Motors Co. should present a restructuring plan for its Opel unit quickly, adding the automaker would have to shoulder most of the cost.

Merkel, who had brokered a deal for Canadian auto parts supplier Magna International Inc. and its Russian bank partner Sberbank to buy Opel, said that the workers needed a concrete solution that offered them job security.

"We expect GM to present a reliable plan for Opel quickly," Merkel told the lower house of parliament today as she laid out her policy agenda for her second term in government.

GM is counting on state aid to help finance its Opel revamp, but Merkel warned: "This solution can only work if GM takes over the lion's share of the restructuring costs, which also means that it has to pay back the bridge loan."

GM said today it had paid back another 200 million euros ($299.6 million) of the 1.5 billion euro bridge loan Germany awarded it to save Opel from being sucked into its U.S. parent's brief bankruptcy.

"We now have an outstanding balance of 600 million euros. We expect to pay the balance before November 30," GM Europe finance chief Enrico Digirolamo said in a statement.

GM has said it needs about 3 billion euros ($4.5 billion) to restructure Opel, although credit rating agency Moody's estimates the sum at $8.5 billion.

More freedom

Opel labor leader Klaus Franz said that GM CEO Fritz Henderson had told him during their meeting today that Opel would receive a "high degree" of autonomy and independence within GM. The union boss has said that autonomy was a precondition for any talks on staff and wage cuts.

Franz said in a statement that Henderson did not agree to labor's demand that Opel return to the legal status of an incorporated German stock company as proof of GM's willingness to relinquish some control.

The next step, according to Franz, was for Detroit's management to present a comprehensive, financially solid business plan for Opel in Europe until 2014.

"We will then decide whether to enter further talks or negotiations," Franz said in a statement.

The labor head, who heavily backed the sale to Magna, had told German magazine Stern that GM's sudden change of heart "froze him solid," from which he was only able to recover from by "downing a bottle of wine."

Frustration is tangible among the 25,000 GM workers in Germany. They had hoped Magna would breathe new life into Opel and had agreed to cost savings as part of the abortive deal.

"We expect the company in the future to be as committed to its European sites as to its American ones," said Merkel.

In St. Petersburg, Sberbank said it would not rule out legal action against GM, which torpedoed months of negotiations and infuriated Opel staff in Germany as well as political leaders in Berlin and Moscow.

"If necessary, we are prepared to defend our position in court. Lawyers are studying the possibility but we have every chance of avoiding the courts," Sberbank CEO German Gref.

Russia was counting on the deal to modernize its outdated domestic auto industry. Moscow has invited Renault to increase its 25 percent stake in carmaker AvtoVAZ.